We propose to continue active participation in the protocol of the NSABP in breast and bowel cancer. Over-all, we have been the fourth largest contributor of patients of these protocols as of 8/31/78. We are currently entering patients into NSABP protocols B-09, C-01, and R-01 and have institutional approval to begin patient entry into protocol B-06 which we plan to do immediately. In addition, we are following 67 living patients from protocols B-04 and B-08. The major objectives of the NSABP are to improve the disease free survival and quality of life for women with operable breast cancer and more recently for patients with colon or rectal cancer. The protocols evaluate the worth of techniques and modalities already employed (B-04); the value of the anti-estrogen drug Tamoxifen combined with chemotherapy and its relation to estrogen and progesterone receptors (B-09); to test the efficacy of segmental mastectomy, with or without radiation, vs., more conventional surgery for survival cosmesis and to study the significance of microscopic multifocal breast tumors (B-06). The rectal protocol (R-01) evaluates whether adjuvant chemotherapy or radiotherapy improves survival over surgery alone. The colon protocol (C-01) assesses the immunotherapy (BCG) vs. surgery alone. All of these protocols are designed to answer important questions about the biology and natural history of these cancers. The method of study is through prospective randomized closely monitored clinical trials.